I was vaping with standard KGO 3.7 volt 1100 mah batteries and started out with average tobacco ejuice in boge LR 2.0 cartomizers.
Then I found I needed more supply of juice so got various Carto tanks; phiniac, triple-Vs, IBTanks, Kir Fanis tanks etc.
I got tired of changing up batteries and waiting for them to charge to use them.
I finally got my first real MOD( to me at least) So studied and got a Saber Touch 3.7/ 6 volt device, soon to be "kicked" I love it. I now use all the tanks above plus use Vivi Novas and now some rebuildables such as the Phoenix RA and the Steam Machine. My favorite juices are The Plume Room tobaccos and Heathers Heavenly Vapes and Goodejuice tobaccos. All are naturally extracted tobaccos. I love it.